Technical Abstract:
We conducted a study in an abandoned warehouse by exposing adult confused flour beetles, Tribolium confusum (Jacqueline DuVal), in 100 by 15 mm plastic Petri dishes containing 0 to 2,000 mg of whole-wheat flour. Nearly all exposed beetles were knocked down after the two-hour exposure interval, however, recovery was affected by position within the warehouse, presence of food material, and whether or not insects were transferred to new dishes. In dishes that did not contain food material, recovery averaged 0 to 20%, with the greatest recovery in those dishes that were in one end of the warehouse, away from the general pattern of aerosol dispersion. Recovery increased with the amount of food material in the Petri dishes, indicating that efficacy was decreased in the presence of food. Recovery also increased when insects were transferred to new dishes, indicating that some residue remained in the dishes from the application. Results show how variation in exposure location and food material at the time of exposure could affect efficacy from aerosol formulations.